Reasonable on 15 February 2008
If by 100% you mean 'collect every meaningless flag, star, or trinket for no real reason' then no - for example those dumb flags in AC can stay unfound.
But I do finish pretty much every game I purchase - a rare exception was Dark Messiah on PC where I got a crashing but near the end a few times and since the game was only okay and not great I just figured I couldn't be bothered to continue.
Try to be reasonable... its easier than you think...
